In known steering wheels comprising a cover cap and a foam casing an expansion joint must be provided between the covering cap and the adjoining foam casing in order to avoid complicated embodiments in which the steering wheel covering cap is integrated into the steering wheel casing and is produced in one piece therewith. The covering cap is movably arranged against a restoring force in the direction of the steering wheel axis for the generation of a horn signal.
In many known embodiments with a separate covering cap, it is difficult and under certain circumstances involves considerable effort, to produce the unavoidable expansion joint between covering cap and steering wheel casing so as to be equally wide throughout, because in this respect the manufacturing tolerances in the manufacture of the steering wheel casing, the covering cap and all the components involved for the fastening of the airbag module to the steering wheel can add up in the most unfavorable case. This leads in practice to expansion joints having distinctly different widths, which are visually unappealing and can not be accepted.
The problem therefore exists of making provision that the width of the unavoidable expansion joints can be maintained within close limits and that the possible accumulation of the manufacturing tolerances can not visually impair in a disadvantageous manner the association between the covering cap and steering wheel casing. The solution which is sought is to lie structurally and financially within the framework of techniques used hitherto, is not to require any additional space and is to be able to be carried out as easily and reliably as possible.